1. Field of the Invention
The present invention relates to a thin film transistor (“TFT”) substrate and a liquid crystal display (“LCD”) apparatus having the TFT substrate. More particularly, the present invention relates to a TFT substrate, an LCD apparatus having the TFT substrate capable of repairing a defective portion such as an electrical opening and increasing productivity of the TFT substrate and a method of repairing the TFT substrate.
2. Description of the Related Art
Generally, an LCD apparatus includes a TFT substrate, a color filter substrate facing the TFT substrate and a liquid crystal layer disposed between the TFT substrate and the color filter substrate. The LCD apparatus receives an electric signal from an external signal source such as a printed circuit board (“PCB”) to display images by changing the electric signal to control electric fields applied to the liquid crystal layer.
FIG. 1 is a top plan layout view illustrating data lines, gate lines, an out lead bonding (“OLB”) pad section and a fan-out section formed on a conventional TFT substrate of the prior art.
Referring to FIG. 1, a conventional TFT substrate of the prior art includes a plurality of gate lines 400 and a plurality of data lines 300 (only a portion of both shown). The data lines 300 extend along a direction that is substantially perpendicular to a longitudinal direction of the gate lines 400, to thereby define a plurality of pixels. Each of the pixels includes a TFT (not shown) and a pixel electrode (not shown). A central area of the TFT substrate, in which the TFTs and the pixel electrodes are formed, corresponds to a display area, and a peripheral area surrounding the display, in which data pads and gate pads are formed, corresponds to a pad area. The data lines 300 and the gate lines 400 extend to the data pads and the gate pads, respectively. The pad area includes a fan-out section 200. The data lines 300 are grouped together, and the data lines 300 of a group move in closer toward each other in the fan-out section 200. The data lines 300 are connected to the OLB pad section 100 to which a tape automation bonded (“TAB”) integrated circuit (“IC”) is attached. Hereinafter, the fan-out section 200 and the OLB pad section 100 are referred to as a pad section.
FIG. 3 is a schematic diagram illustrating a conventional OLB pad section and wirings of a fan-out section of the prior art.
FIG. 3 illustrates a signal transfer procedure from a driver circuit to a display area. An electrical signal provided from the driver circuit is transferred to the data lines 300 in the display area through the OLB pad section 100 and the fan-out section 200.
A color filter substrate (not shown) combined with the TFT substrate includes a color filter and a common electrode. The color filter substrate is smaller in size than the TFT substrate, such that the pad area, in which the gate pads and the data pads are formed, is exposed when the TFT substrate and the color filter substrate are combined with each other.
When the data lines 300 or the gate lines 400 are electrically opened in the fan-out section 200, a pixel defect or a line defect may be generated in the display area.
According to a conventional LCD apparatus of the prior art, in order to repair a wiring that is electrically opened, a repair wiring may be additionally formed to connect portions of the electrically opened wiring, or the portions of the electrically opened wiring are directly connected to each other.
FIG. 4 is a picture illustrating an electrical open in a conventional fan-out section 200 of the prior art.
Referring to FIG. 4, an electrical open 100a may be generated in the wirings not only in the fan-out section 200 but also in the OLB pad section 100. When the wirings are electrically opened in both the fan-out section 200 and in the OLB pad section 100, the conventional methods cannot be applied to repair the wirings of the fan-out section 200 and the OLB pad section 100. Therefore, a method for repairing electrically opened wiring in a fan-out section or in a OLB pad section is required.